CVE-2021-27393

A vulnerability has been identified in Nucleus NET (All versions), Nucleus RTOS (versions including affected DNS modules), Nucleus ReadyStart (All versions < V2013.08), Nucleus Source Code (versions including affected DNS modules), VSTAR (versions including affected DNS modules). The DNS client does not properly randomize UDP port numbers of DNS requests. That could allow an attacker to poison the DNS cache or spoof DNS resolving.

Source: CVE-2021-27393